Except “Assistance” isn’t about the powerful Daniel Weisinger, who puts his staff through the nine circles of hell. We never see or hear him, and we don’t even know what he does. He could be Steve Jobs, Simon Cowell or Anna Wintour.

What we do see is how Daniel makes his assistants sacrifice their personal lives, friends and family for his needs. As they work around the clock in their downtown office — meticulously rendered by David Korins — we watch them grovel on the receiving end of one abusive call after another.

It’s hard not to cringe as these indentured servants debase themselves for the privilege of being corrected, mocked and vilified.

“Working for Daniel is like living the last 30 minutes of ‘Goodfellas’ over and over again,” Nick (the virtuosic Michael Esper) tells new recruit Nora (a deliciously daffy Virginia Kull).

And he doesn’t mean that as a bad thing.

Nora quickly gets with the program — “Insults build character,” she rationalizes. Similarly, Justin (Bobby Steggert, from “Ragtime”) works through a broken foot, while a new British recruit, Jenny (Amy Rosoff), proves cool-headed and manipulative.

In this world, pruning the weak is as important as promoting the strong. The dedicated Heather (Sue Jean Kim) exhausts herself 24/7, but requesting time off for her uncle’s funeral proves to be an outrageous demand. “The Heathers of the world don’t last longer than six weeks,” Nick says. “They die right after they’re born, like cloned sheep.”

Headland can a unleash rapid-fire comic blitzkrieg with a spot-on ear for the way 20-somethings relate to each other. And this Playwrights Horizons production plays to her strengths.

Under the speedy direction of Trip Cullman, who also helmed “Bachelorette,” the top-notch cast masters these hyperverbal characters’ aggressive irony and mock levity, as well as their fear of betraying any weaknesses.

There are few options for those willing slaves. Some give up. Others elbow their way up to middle management.

Only the rogues creating chaos to better exploit it can hope to reach the top. As the explosive, highly satisfying final scene proves, they also make for exciting theater.